Regarding Helmholtz and Steinway's relationship concening the duplex scale I would like to refer to two items. #1 page 183 on Sensations....in which the exact duplex scale theory is outlined. Virtually all duplex scales of all pianos starting with S's are based on the data of this page. All you hvae to do is check the duplex scales in relation to the chart to confirm H's relation to S in this matter 2. The letters of correspondance between Steinway and helmholtz specifically describe what CFT learned from HH and his efforts to apply this knowledge I must say at this juncture, my colleagues, that the efforts to discuss the matter seem to be concealing a trepidation in dealing with it. In other words, my feeling is that it might be more valuable to try applying the principles and actually take a whack at tuning some duplex scales, than trying to rationalize them out of the millions of pianos that have them. Duplexdan.
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